Phoenix, AZ: 480-944-6731

8 a.m. to 5 p.m.

Mountain time, Monday through Friday

Proton Beam Radiation: Innovation for Highly Precise Cancer Treatment

When choosing cancer care, you want access to all the most innovative options to help you achieve your goals and best outcomes. Proton beam therapy at Mayo Clinic in Arizona is an innovative new alternative to traditional radiation.

We use pencil beam scanning, the most precise form of proton therapy. This enables us to target tumors with a radiation beam that is only a few millimeters wide.

Benefits of precision.

Significant benefits of proton beam therapy include:

  • Tumor tissue is targeted more accurately.
  • Healthy tissue has less radiation exposure.
  • There are fewer short- and long-term side effects from radiation exposure, such as development of new cancers.

Treatment for children and adults.

Proton beam therapy is proven beneficial in treating both children and adults for many tumors including:

  • Brain
  • Breast
  • Esophageal
  • Eye
  • Gastrointestinal
  • Gynecological
  • Head and neck
  • Liver
  • Lung
  • Lymphoma
  • Pancreatic
  • Prostate
  • Soft tissue
  • Spine
  • Many pediatric cancers

Expert team works together for you.

Mayo Clinic has the largest proton center in the United States and is a designated Comprehensive Cancer Center by the National Cancer Institute. You’ll have access to the latest, most innovative cancer treatments. You’ll also have a multidisciplinary team of experts focused on meeting your goals and needs.

No referral needed.

We are now taking appointments in Arizona. You do not need a referral from a doctor.

When it's time to find answers, you know where to go.

Contact us to request an appointment.

5777 E. Mayo Blvd. 

Phoenix, AZ 85054 


480-944-6731

8 a.m. to 5 p.m.

Mountain time, Monday through Friday

Patient Testimonials

My doctors at Mayo Clinic understood my concerns and have been great about preserving my quality of life.

– Jessie

Mayo Clinic's Approach to Proton Beam

Proton beam therapy is a very rare form of radiation therapy in this country and throughout the world. Just to give an idea of the scarcity, proton beam therapy is about one half of 1% of all the radiation therapy delivered in this country. It's only available at about 25 centers in the country, in comparison, X-ray therapy or more traditional linear accelerators are available at about 4,000 centers in the country.


Most patients have had an X-ray for something. A dental X-ray, a chest X-ray. X-rays go in one side of the body and come out of the other side of the body. They're very effective at killing cancer when we turn the dial all the way up, and it's what we call ionizing radiation. Protons are different. They're a charged particle.


In fact, all a proton is its hydrogen. It's the H of H2O. It has a positive charge, so we can accelerate the proton to whatever energy we need. Imagine it's like a depth charge. So in that same situation, the proton will go a set distance, and it will basically release all its energy at that point. It's always challenging when patients have to decide what type of treatment is best for them, and that's why at Mayo Clinic, they don't have to make that decision alone.


Speaking to the general principles of Mayo Clinic, I think it's always important to remind patients and providers that all the providers at Mayo Clinic are salaried. There's no bonuses for treating more patients or prescribing more treatment, so we really have removed any financial incentives from the treatment algorithm, which I think is good for the patients to know. Speaking from a radiation perspective, the first question we ask is, will radiation therapy benefit this particular patient, because it may not, and if that's the case, we won't offer it.


But if radiation does benefit the patient, then we have access to every tool in the box for the field of radiation oncology, whether it be X-ray therapy, proton beam, radio surgery, or if it's taking these tools and working with medical oncologists, we can do everything-- all the treatments in the spectrum are available at our disposal. The first thing to do when a patient is diagnosed is I tell that patient, this is a scary moment. We understand that, to take a deep breath. I think they should consider-- they should strongly consider-- going to the Mayo Clinic web site. We have an amazing amount of information on the Mayo Clinic web site, and if they feel so inclined, to reach out to us because it's very easy to do, and then from there, we can work with the patients to see if actually coming to Mayo Clinic makes the most sense for them.


I'm not naive, and I'm very respectful of the quality of medical care of physicians and surgeons in this country and really around the world. We have excellent physicians at Mayo Clinic. I know there are several excellent physicians though all over. I get that, and I am very respectful of that. I think what really makes us good is that we're much stronger together than as individuals.

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